Attorney General Eric Holder will launch a Justice Department investigation of St. Louis County police departments (including Ferguson’s police department) to determine if they are engaging in consistent violations of constitutional and federal rights, reports indicate. The investigation will be distinct from the Justice Department inquiry into Michael Brown’s death, and will follow similar investigations into other police departments nationwide. From the Washington Post:

The investigations can be collaborative arrangements, with police chiefs encouraging the thorough reviews, training recommendations and reform ideas the civil rights division proposes.

But:

An investigation often ends up in a lawsuit brought by the Justice Department against a local police department. Justice Department officials could also reach a settlement with the police department, which includes a consent decree and federal monitoring, as was the case with police forces in New Orleans and San Juan, Puerto Rico.

The Post reports that five current and one former Ferguson police officer “face pending federal lawsuits claiming they used excessive force,” while the Associated Press notes that a widely discussed 2013 Missouri investigation found that Ferguson officers stopped and arrested black drivers nearly twice as often as white drivers even though “contraband” was more often discovered during stops of the white drivers.